Outline extended git annex sync semantics in the documentation

1 files changed, 9 insertions, 4 deletions

diff --git a/doc/git-annex.mdwn b/doc/git-annex.mdwn
index 39fe5d99e..2c0e23e9c 100644
--- a/doc/git-annex.mdwn
+++ b/doc/git-annex.mdwn
@@ -122,13 +122,18 @@ subdirectories).
 
 * sync
 
-  Use this command when you want to synchronize the local repository
-  with its default remote (typically "origin"). The sync process involves
-  first committing all local changes, then pulling and merging any changes
-  from the remote, and finally pushing the repository's state to the remote.
+  Use this command when you want to synchronize the local repository with
+  one or more other repositories. The sync process involves first committing
+  all local changes, then fetching and merging the `synced/master` and the
+  `git-annex` branch from the remote repositories and finally pushing the
+  changes back to these remote branches.
   You can use standard git commands to do each of those steps by hand,
   or if you don't want to worry about the details, you can use sync.
 
+  By default, `git annex sync` will sync all remote repositories that have a
+  `synced/master` branch. If you want to include/exclude a repository from
+  this list, just create or delete this branch.
+
   Note that sync does not transfer any file contents from or to the remote.
 
 * addurl [url ...]